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2.
目前的移动自组网研究主要针对运动速度较慢的地面网络。本文研究由高速节点组成的高动态移动自组网的路由协议,提出了一个结合表驱动路由和地理位置路由的混合路由协议TOPOS,在局部使用表驱动路由加快数据包的转发,而在全局使用地理位置路由以适应快速变化的网络拓扑。在OPNET仿真平台上对TOPOS和已有的AODV及GRP协议的性能比较表明,TOPOS对于节点的运动速度和网络规模具有更好的适应性。 相似文献
3.
Vehicular ad-hoc networks (VANETs) is drawing more and more attentions in intelligent transportation system to reduce road accidents and assist safe driving. However, due to the high mobility and uneven distribution of vehicles in VANETs, multi-hops communication between the vehicles is still particularly challenging. Considering the distinctive characteristics of VANETs, in this paper, an adaptive routing protocol based on reinforcement learning (ARPRL) is proposed. Through distributed Q-Learning algorithm, ARPRL constantly learns and obtains the fresh network link status proactively with the periodic HELLO packets in the form of Q table update. Therefore, ARPRL’s dynamic adaptability to network changes is improved. Novel Q value update functions which take into account the vehicle mobility related information are designed to reinforce the Q values of wireless links by exchange of HELLO packets between neighbor vehicles. In order to avoid the routing loops caused in Q learning process, the HELLO packet structure is redesigned. In addition, reactive routing probe strategy is applied in the process of learning to speed up the convergence of Q learning. Finally, the feedback from the MAC layer is used to further improve the adaptation of Q learning to the VANETs environment. Through simulation experiment result, we show that ARPRL performs better than existing protocols in the form of average packet delivery ratio, end-to-end delay and number hops of route path while network overhead remains within acceptable ranges. 相似文献
4.
Many existing reactive routing algorithms for mobile ad-hoc networks use a simple broadcasting mechanism for route discovery
which can lead to a high redundancy of route-request messages, contention, and collision. Position-based routing algorithms
address this problem but require every node to know the position and velocity of every other node at some point in time so
that route requests can be propagated towards the destination without flooding the entire network. In a general ad-hoc network,
each node maintaining the position information of every other node is expensive or impossible. In this paper, we propose a
routing algorithm that addresses these drawbacks. Our algorithm, based on one-hop neighborhood information, allows each node
to select a subset of its neighbors to forward route requests. This algorithm greatly reduces the number of route-request
packets transmitted in the route-discovery process. We compare the performance of our algorithm with the well known Ad-hoc
On-demand Distance Vector (AODV) routing algorithm. On average, our algorithm needs less than 12.6% of the routing-control
packets needed by AODV. Simulation results also show that our algorithm has a higher packet-delivery ratio and lower average
end-to-end delay than AODV. 相似文献
5.
Multipath routing has been proposed to improve performance of mobile ad-hoc networks (MANETs). However, due to: (1) nodes lacking of network interface and (2) route coupling, using multiple paths concurrently in conventional single channel MANETs rarely exhibit performance gain. To improve performance, an ad-hoc routing protocol (and its extension) that utilizes multiple homogeneous network interface is proposed in this paper. Unlike other related multi-channel routing protocols, channels are not assigned. Instead, nodes are allowed to make use of all available channels they are tuned to. In the base protocol, nodes estimate channel conditions by monitoring their network interface queues and distribute data packets to different channels and next-hops according to their conditions. In the extended protocol, estimated channel condition at a node is further propagated to neighboring nodes by piggybacking channel condition information in data packets. With overhearing, other nodes can retrieve this information to make better next-hop selections. Extensive simulation studies show that our protocol outperforms other related multi-channel routing protocols. 相似文献
6.
Wireless Personal Communications - Ad-hoc social networks are required to strengthen local communication between people. Mobile ad-hoc social networks have emerged as self-configuring and... 相似文献
7.
本文针对多媒体传感器网络中三类基本服务:异常事件告警服务、信息查询服务以及流媒体查询服务,分析了不同服务的QoS需求,并抽象出多媒体传感器网络QoS路由模型.进而,利用改进的蚁群算法,设计了一个基于蚁群优化的服务感知路由算法ASAR (Ant-colony optimization based Service Aware Routing).本文设计服务感知的路由协议,旨在依据各类媒体数据包不同的QoS需求,选择相应的路由以合理利用全网资源、提高网络性能.最后,我们通过NS2仿真表明了较其他路由算法,本文提出的方法能够为多媒体传感器网络的多种服务提供更好的QoS保障,同时,比传统的蚁群算法具有更好的收敛性. 相似文献
8.
Wireless Personal Communications - During the last two decades, there has been a tremendous growth in the use of MANETs, not only due to the development of the technology but also due to their high... 相似文献
9.
随着无线传感器网络在移动环境中广泛应用,移动环境下降低能耗成了传感网络研究的热点.通过研究移动环境下的各种路由协议,并结合LEACH协议自身存在的问题,提出了一种支持移动的簇头多跳的路由算法.该协议充分考虑了剩余能量、速度和距离,以及簇头选取和簇的构成方法,提出新的权值函数,从而有效地支持节点移动.仿真结果表明,该协议有效地均衡了节点能耗,提高了能量利用率,延长了网络寿命. 相似文献
10.
Wireless Personal Communications - Recent reports show that the millions of people killed each year in the road accidents are due to high density vehicles and traffic environment. The road traffic... 相似文献
11.
In the wireless ad-hoc network management, Quality of Service (QoS) is an important issue. Along with the QoS ensuring, another desirable property is the network reliability. In data communications, multi-path routing strategy can cope with the problem of traffic overloads while balancing the network resource consumption. In this paper, we propose a new multipath routing algorithm for QoS-sensitive multimedia services. Based on the ant colony optimization technique, the proposed algorithm can establish effective multi-paths to enhance the network reliability. According to the load balancing strategy, data packets are adaptively distributed through the established paths while maintaining an acceptable level of QoS requirement. The most important feature of the proposed approach is its adaptability to current traffic conditions. Simulation results indicate the superior performance of the proposed algorithm, while other schemes cannot offer such an attractive performance balance. 相似文献
12.
Maximizing network lifetime is the main goal of designing a wireless sensor network. Clustering and routing can effectively balance network energy consumption and prolong network lifetime. This paper presents a novel cluster-based routing protocol called EECRAIFA. In order to select the optimal cluster heads, Self-Organizing Map neural network is used to perform preliminary clustering on the network nodes, and then the relative reasonable level of the cluster, the cluster head energy, the average distance within the cluster and other factors are introduced into the firefly algorithm (FA) to optimize the network clustering. In addition, the concept of decision domain is introduced into the FA to further disperse cluster heads and form reasonable clusters. In the inter-cluster routing stage, the inter-cluster routing is established by an improved ant colony optimization (ACO). Considering factors such as the angle, distance and energy of the node, the heuristic function is improved to make the selection of the next hop more targeted. In addition, the coefficient of variation in statistics is introduced into the process of updating pheromones, and the path is optimized by combining energy and distance. In order to further improve the network throughput, a polling control mechanism based on busy/idle nodes is introduced during the intra-cluster communication phase. The simulation experiment results prove that under different application scenarios, EECRAIFA can effectively balance the network energy consumption, extend the network lifetime, and improve network throughput. 相似文献
13.
The dynamic nature of mobile nodes of ad hoc network is mostly affected by security problems which reduce data forwarding rate in multimedia sources. Due to the rapid growth of wireless applications, the different multitalented routing protocols are proposed in recent years. But the recent protocols are not efficient for multimedia applications, till now, specific security aware routing protocols are not proposed for multimedia data transfers. In this paper, we proposed trust enhanced cluster based multipath routing (TECM) algorithm. We use energy efficient PSO algorithm used to create cluster formation and cluster head, super cluster head are selected from trust values, which compute form proposed TECM algorithm. The multi trust factors are used for trust computation, such as frame/packet loss ratio, frame/packet forward energy, frame/packet receiving energy, routing overhead, received signal strength, frame/packet forward rate, average forward delay and protocol deviation flag. We then combine proposed TECM algorithm with standard multipath OLSR protocol (TECM-OLSR) to analyze the performance of proposed algorithm. The simulated results show that proposed TECM-OLSR protocol is very effective in terms of loss and delivery rate, delay, routing overhead and network lifetime compare to FPNT-OLSR. 相似文献
14.
Wireless Personal Communications - In Wireless Sensor Network (WSN), the lifetime optimization based on minimal energy consumption and security are the crucial issues for the effective design of... 相似文献
15.
In this paper, we present a “spatiotemporal multicast”, called a “mobicast”, protocol for supporting applications which require
spatiotemporal coordination in vehicular ad hoc networks (VANETs). The spatiotemporal character of a mobicast is to forward
a mobicast message to vehicles located in some geographic zone at time t, where the geographic zone is denoted as zone of relevance (ZOR). Vehicles located in ZOR at the time t must keep the connectivity to maintain the real-time data communication between all vehicles in ZOR. The connectivity is
kept of all vehicles in ZOR through the vehicular ad hoc networks (VANETs). The connectivity of ZOR is lost if any vehicle
in ZOR suddenly accelerates or decelerates its velocity. The temporal network fragmentation problem is occurred such that
vehicle in ZOR cannot successfully receive the mobicast messages. To solve the problem, a new mobicast protocol is presented
in this work to successfully disseminate mobicast messages to all vehicles in ZOR via a special geographic zone, called as
zone of forwarding (ZOF). The main contribution of this work is to develop a new mobicast routing protocol to dynamically
estimate the accurate ZOF to successfully disseminate mobicast messages to all vehicles in ZOR. To illustrate the performance
achievement, simulation results are examined in terms of dissemination successful rate, packet overhead multiplication, packet
delivery delay, and throughput. 相似文献
16.
In Mobile Ad-hoc Networks (MA-NETs), routing protocols directly affect various indices of network Quality of Service (QoS), so they play an important role in network performance. To address the drawbacks associated with traditional routing protocols in MANETs, such as poor anti-fading perfor-mance and slow convergence rate, for basic Dynamic Source Routing (DSR), we propose a new routing model based on Grover’s sear-ching algorithm. With this new routing model, each node maintains a node vector function, and all the nodes can obtain a node probability vector using Grover’s algorithm, and then select an optimal routing according to node probability. Simulation results show that compared with DSR, this new routing protocol can effectively extend the network lifetime, as well as reduce the network delay and the number of routing hops. It can also significantly improve the anti-jamming capa-bility of the network. 相似文献
17.
Ad Hoc网络中的节点是由电池供电,整个网络是一个能量受限系统,如何节省节点的能量,尽可能延长网络的可操控时间逐渐成为衡量路由协议性能的重要指标.基于移动节点能量的不同级别,采取不同的转发策略,提出了一种基于能量感知的Ad Hoc网络路由协议--EARP.并与AODV协议进行了性能比较,仿真结果显示,EARP具有较低的能耗,较长的网络存活时间. 相似文献
18.
Wireless Personal Communications - Mobile adhoc network (MANET) is an autonomous network, comprising several hosts which are linked to one another via wireless connections. Since the nodes in MANET... 相似文献
19.
Wireless Sensor Network (WSN) has many sensor nodes that connect with sync nodes. The sensor node's power is a limitation. The expense and difficulty of battery charging and replacement affect sensor node life and network length. Clustering reduces the cost of internal cluster communication, thereby conserving energy. Generally, researchers seek for low energy usage via providing data to monitor the cluster's energy use. Many of them are tied to network length. The Ant Group (TAS) technique is the first notion for establishing a cluster using the OC algorithm that saves electricity. Next, we use improved myopia (IM) to find the cluster head (CH). This minimises the number of clusters and the expense of internal communications. The proposed OC-TAS-IM algorithm attempts to enhance energy efficiency. In the network. The route is also conducted using a special algorithm in the low energy adaptive cluster range (reach). It contains Network Simulator implementation and simulation experiments to test specific OC-TAS-IM algorithms (NS2). Because of optimum clustering, the OC-TAS-IM method is stable in terms of energy clustering and grid lifespan. 相似文献
20.
In Mobile IP, the signaling traffic overhead will be too high since the new Care-of-Address (CoA) of the mobile node (MN)
is registered all the way with the home agent (HA) whenever the MN has moved into a new foreign network. To complement Mobile
IP in better handling local movement, several IP micro protocols have been proposed. These protocols introduce a hierarchical
mobility management scheme, which divides the mobility into micro mobility and macro mobility according to whether the host's
movement is intra-domain or inter-domain. Thus, the requirements on performance and flexibility are achieved, especially for
frequently moving hosts. This paper introduces a routing protocol for multicast source mobility on the basis of the hierarchical
mobile management scheme, which provides a unified global architecture for both uni- and multicast routing in mobile networks.
The implementation of multicast services adopts an improved SSM (Source Specific Multicast) model, which combines the advantages
of the existing protocols in scalability and mobility transparency. Simulation results show that the proposed protocol has
better performance than the existing routing protocols for SSM source mobility. 相似文献
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